How to Connect the Red and Black Test Leads When Measuring Current with a Multimeter
Insert the red probe into the socket labeled "mA" or "10A" on the multimeter, and then insert the black probe into the "COM" socket. This is because the "mA" socket is used to measure small currents, while the "10A" socket is used to measure large currents.
Check whether the current level of the tested circuit is greater or less than 200mA. If the current is less than 200mA, the knob of the meter can be selected to the "mA" range. At this time, the red probe should be inserted into the multimeter current socket "mA" or "A", and the black probe should be inserted into the COM.
If the current is greater than 200mA, we need to select the "10A" range gear. At this point, the red probe should be inserted into the current socket "10A" of the multimeter, while the black probe should be inserted into the COM.
After ensuring the correct wiring, we can start measuring the current. Place the ammeter in the series position of the circuit under test, that is, connect the red probe to the current inlet and the black probe to the current outlet.
After ensuring that the wiring is not loose, turn on the circuit switch and allow the current to pass through the measurement circuit. At this point, the pointer or display screen on the multimeter will show the current value of the tested circuit.
How to use the resistance range of a multimeter
The resistance measurement of a multimeter is a common measurement method. The following is the usage method of the resistance range:
Firstly, confirm that the measured resistor has been disconnected from the circuit. This is because resistance is an electrical quantity, and if other components are present in the circuit, they may interfere with the test results.
Select the knob to the "Ω" or "R" range gear, which is the dedicated gear for measuring resistance.
Connect the wires correctly using red and black probes. Insert the red probe into the "Ω" or "R" socket of the multimeter, while the black probe should be inserted into the COM socket.
Connect the red probe to one end of the measured resistor and the black probe to the other end.
Ensure safe and reliable wiring, and then read the resistance value. At this point, the pointer or display screen on the multimeter will show the resistance value of the measured resistor.
After the measurement is completed, remember to return the knob to its initial position to avoid damaging the meter.
It should be noted that when measuring high resistance values, it may be necessary to select the knob to a higher range gear. In addition, when measuring resistance, try to avoid contact with metal probes as much as possible. If precise resistance measurement is required, attention should also be paid to the influence of ambient temperature, as the resistance value will change with temperature.
